Apparatus for the extraction of blanks from a blank magazine

Abstract

For the production of packs from (thin) cardboard, blanks (10) are prefabricated and stored as a blank stack (16) in a blank magazine (17) for processing. An extraction member (20) serves for extracting the individual blanks from the underside of the blank magazine (17) and transports the blanks into a discharge-conveyor plane (21). The extraction member (20) is transportable over a small acute angle as a result of a pivoting movement, in order to move the blanks from the blank stack (16) into the discharge-conveyor plane (21). Furthermore, the extraction member (20) is so designed that, immediately after the discharge-conveyor plane (21) is reached, it can be conveyed into an initial position as a result of sideways movements of holding members (23,24) without being disturbed by the blank (10). In the discharge-conveyor plane (21), the blank (10) is fed to drawer rollers (51, 52 etc) by a pushing-off member (pushing fingers 57,58).

What is claimed is: 
     
       1. Apparatus for the extraction of pack blanks of thin cardboard from an underside of a blank stack located in a blank magazine of a packaging machine, the extracted blanks being introducible into a discharge-conveyor located in a plane (21) extending underneath the blank stack, characterized: in that, for the extraction of the blanks (10), there is an extraction member (20) comprising holding members (23, 24) which are subjected to a vacuum and by which a blank (10) can be grasped in its lateral regions on a free lower side of the blank, and, as a result of a downward movement of the blank, transported to and deposited on the discharge-conveyor plane (21);   in that said extraction member produces said downward movement;   in that the holding members (23, 24) are elongate and arm-like and in a lower position are rotatable away from the deposited blank (10) in opposite directions and are movable into an upper receiving position for grasping a further blank (10);   in that there are means for rotating and moving said holding members;   in that the holding members (23, 24) have offset bearing faces which engage the blank (10) and which are in the form of plate-like wings (25); and   in that said means for rotating causes the holding members (23, 24) respectively to rotate about an axis (36) extending offset relative to the wings (25), in such a way that, as a result of the rotation, the holding members (23, 24) are rotated away from the deposited blank (10) in said opposite directions.   
     
     
       2. Apparatus according to claim 1, characterized in that the holding members (23, 24) are mounted rotatably at first ends thereof by respective shaft pieces (36) located in pivot bearings (37) forming part of a transversely directed shaft (22) for pivotally driving the holding members (23, 24) over an acute angle. 
     
     
       3. Apparatus according to claim 1, characterized in that said extraction member (20) has, on a side facing the blank (10), at least six suction bores (26, 27, 28) arranged in two rows adjacent respective pairs of lateral folding tabs (12, 13, 14) of the blank (10). 
     
     
       4. Apparatus according to claim 3, characterized in that, for grasping blanks (10) of a hinge-lid pack, the suction bores (26, 27, 28) are arranged in the wings (25) in such a way that two outer side tabs (12), two inner side tabs (13) and two lid side tabs (14) can be grasped by respective ones of said suction bores (26, 27, 28). 
     
     
       5. Apparatus according to claim 1, characterized in that the wings (25) are arranged offset relative to the axis of rotation of the holding members (23, 24), in such a way that, as a result of rotation of the wings (25) into an upright plane, the wings are moved completely out of a vicinity of the blank (10). 
     
     
       6. Apparatus for the extraction of pack blanks of thin cardboard from an underside of a blank stack located in a blank magazine of a packaging machine, the extracted blanks being introducible into a discharge-conveyor located in a plane (21) extending underneath the blank stack, characterized: in that, for the extraction of the blanks (10), there is an extraction member (28) comprising holding members (23, 24) which are subjected to a vacuum and by which a blank (10) can be grasped in its lateral regions on a free lower side of the blank, and, as a result of a downward movement of the blank, transported to and deposited on the discharge-conveyor plane (21);   in that said extraction member produces said downward movement;   in that the holding members (23, 24) are elongate and arm-like and in a lower position are rotatable away from the deposited blank (10) in opposite directions and are movable into an upper receiving position for grasping a further blank (10);   in that there are means for rotating and moving said holding members; and   in that, during the extraction of a blank (10) from the blank magazine (17), after the blank has been grasped, it is first brought into an initial arched position as a result of oppositely directed rotational movements of the holding members (23, 24), and then moved downwards and is deposited in the discharge-conveyor plane (21), the holding members (23, 24) being pivotable away from the blank (10) immediately after the discharge-conveyor plane (21) is reached and, as a result of an upward movement, movable back into the initial position.   
     
     
       7. Apparatus for the extraction of pack blanks of thin cardboard from an underside of a blank stack located in a blank magazine of a packaging machine, the extracted blanks being introducible into a discharge-conveyor located in a plane (21) extending underneath the blank stack, characterized: in that, for the extraction of the blanks (10), there is an extraction member (28) comprising holding members (23, 24) which are subjected to a vacuum and by which a blank (10) can be grasped in its lateral regions on a free lower side of the blank, and, as a result of a downward movement of the blank, transported to and deposited on the discharge-conveyor plane (21);   in that said extraction member produces said downward movement;   in that the holding members (23, 24) are elongate and arm-like and in a lower position are rotatable away from the deposited blank (10) in opposite directions and are movable into an upper receiving position for grasping a further blank (10);   in that there are means for rotating and moving said holding members; and   in that the blank (10), after reaching the discharge-conveyor plane (21), can be transported away by a first conveying member in the form of a pusher member with pushing fingers (57, 58) for grasping the blank (10) on a rear side thereof.   
     
     
       8. Apparatus according to claim 7, characterised in that the pushing member (57, 58) is arranged between the holding members (23, 24) of the extraction member (20). 
     
     
       9. Apparatus for the extraction of pack blanks of thin cardboard from an underside of a blank stack located in a blank magazine of a packaging machine, the extracted blanks being introducible into a discharge-conveyor located in a plane (21) extending underneath the blank stack, characterized: in that, for the extraction of the blanks (10), there is an extraction member (28) comprising holding members (23, 24) which are subjected to a vacuum and by which a blank (10) can be grasped in its lateral regions on a free lower side of the blank, and, as a result of a downward movement of the blank, transported to and deposited on the discharge-conveyor plane (21);   in that said extraction member produces said downward movement;   in that the holding members (23, 24) are elongate and arm-like and in a lower position are rotatable away from the deposited blank (10) in opposite directions and are movable into an upper receiving position for grasping a further blank (10);   in that there are means for rotating and moving said holding members in said opposite directions; and   in that the holding members (23, 24) are mounted rotatably at first ends thereof by respective shaft pieces (36) located in pivot bearings (37) forming part of a transversely directed shaft (22) for pivotally driving the holding members (23, 24) over an acute angle.   
     
     
       10. Apparatus according to claim 2 or 4, characterized in that arranged at ends of the shaft pieces (36) are drive members for executing rotational movements about longitudinal axes of the holding members (23, 24), said drive members comprising gearwheels (38) which are in engagement with toothed quadrants (41) of a rotary sleeve (40) mounted on said shaft (22). 
     
     
       11. An apparatus for the extraction of pack blanks (10) of thin cardboard from an underside of blank stack (16) located in a blank magazine (17) of a packaging machine, comprising: a blank magazine (17);   an extraction member (20) which is provided with a vacuum, for extracting the blanks (10) from the blank magazine (17), and by which the blanks (10) are grasped at a free lower side of the blanks;   wherein the extraction member (20) comprises only two spaced-apart, elongate, arm-like holding members (23, 24) which grasp only lateral portions of each blank (10);   a discharge-conveyor plane (21) located underneath said blank magazine (17);   means for downwardly moving said extraction member to transport a grasped blank out of said blank magazine (17) and into said discharge-conveyor plane;   conveying member means, located in a vicinity of said discharge-conveyor plane (21) and between the elongate and arm-like holding members (23, 24), for discharging the blanks in a conveying direction away from said holding members (23, 24);   means for pivotally moving said extraction member (20) from an upper initial position at said underside of the blank stack (16) in said blank magazine (17) to a lower position in said discharge-conveyor plane (21) which is oblique and downwardly inclined in said conveying direction of the extracted blank; and   means for rotating said holding members (23, 24) away from the blank in opposite directions to release the blank (10) in said lower position in said discharge-conveyor plane (21), and for moving said holding members (23, 24) back to said upper position for extracting another blank from said blank magazine (17).   
     
     
       12. An apparatus for the extraction of peak blanks (10) of thin cardboard from an underside of blank stack (16) located in a blank magazine (17) of a packaging machine, comprising: a blank magazine (17);   an extraction member (20) which is provided with a vacuum, for extracting the blanks (10) from the blank magazine (17), and by which the blanks (10) are grasped at a free lower side of the blanks;   wherein the extraction member (20) comprises only two spaced-apart, elongate, arm-like holding members (23, 24) which grasp only lateral portions of each blank (10);   a discharge-conveyor plane (21) located underneath said blank magazine (17);   means for downwardly moving said extraction member to transport a grasped blank out of said blank magazine (17) and into said discharge-conveyor plane; and   conveying member means, located in a vicinity of said discharge-conveyor plane (21) and between the elongate and arm-like holding members (23, 24), for discharging the blanks in a conveying direction away from said holding members (23, 24);   wherein, during the extraction of a blank (10) from the blank magazine (17), after the blank has been grasped, it is first brought into an initial arched position as a result of oppositely directed rotational movements of the holding members (23, 24), and then moved downwards by said extraction member (20) and is deposited in the discharge-conveyor plane (21), the holding members (23, 24) being pivotable away from the blank (10) immediately after the discharge-conveyor plane (21) is reached and, as a result of an upward movement, movable back into the initial position.